This invention relates to a cementitious building material that is self sustaining. More particularly, this invention relates to a cementitious building material that is hardened by means of a cured resinous material.
Gypsum is a white or yellowish-white mineral having the chemical formula CaSO.sub.4.XH.sub.2 O and is widely used in its hydrated or calcined (non-hydrated) form as a filler for paints and candies, as a fertilizer, as an additive to soften portland cement, as plaster of Paris and for making plasterboard and wallboard.
When used for making plaster-or wallboard the gypsum is so soft that is must be contained between heavy sheets of paper.
Other cementitious material include portland cement, plasters, mortars and carbonates (limes), and combinations of the same with or without fillers. These materials are often too heavy to be used practically as prefabricated building materials.
Foamed plastics are known to have excellent insulative properties and are known to have been used in the form of foamed panels in the making of prefabricated building. When used for this purpose a structure having inner and outer walls is first constructed and the plastic is then foamed into the interior space between the wall.
Due to the relative softness of gypsum, the weight of other cementitious materials and the characteristic properties of foamed resins, such as urea-formaldehyde, phenol formaldehyde, polyurethane and polystyrene foams, they have not proven suitable in and of themselves as prefabricated building materials but have required that outer coverings or walls be present.